By Klaus Holm Nissen, Project Manager, A2SEA
SEA INSTALLER and her crew have just installed the eighteenth of 32 MHI Vestas V164-8.0 MW turbines at Burbo Bank Extension. So far, we’ve made excellent progress, despite having to work with a lot of new, specialised lifting equipment for these large components. With the learning curves behind us, and if the weather continues to cooperate as nicely as it has to date, we expect to be finished mid to late December.
This is the first time we’ve installed a MHI Vestas V164-8.0 MW turbine. Yet the task presents relatively few challenges for us. Perhaps the most difficult part of the project, seen from A2SEA’s point of view, is the sea bed in the area. With a lot of clay and sand, as well as some silt, it’s a tricky task to jack up securely. That kind of surface composition can be very sticky, which initially had us thinking we might have problems retracting the legs. But it didn’t turn out to be much of a problem. There were, of course, some extended pre-load periods in order for us to compress the soil sufficiently and make sure it was able to support the vessel – even in a storm.
Maneuvering in the area has been relatively simple, too. In fact, we used the exact same vessel for West of Duddon Sands, gaining experience of the transit route and the surrounding seas. Returning to Belfast harbour does, however, require both sophisticated DP2 positioning equipment and vast skill on the ship’s master’s side. That’s because a stone seabed has been specially constructed to enable us to jack up at the quayside (the existing soil would have been unsuitable) and we need to place the vessel’s feet in the exact same spot – within centimetres – in order to maintain this new structure.
As usual, there are plenty of people on board SEA INSTALLER. There’s our crew of 25, five representatives from DONG Energy, and 30 cabins for the installation crew.
This is also a strongly local operation. Mobilisation was performed at the Cammell Laird yard in Liverpool, where MHI Vestas’ new blade stack system required a different approach to sea fastenings. And we have a site office in Belfast which is manned around the clock. It’s also the first time A2SEA has worked with MHI Vestas and it’s safe to say that the project has been successful and enjoyable for all parties.Like this post? Subscribe now and get notified about new content!